Valve bag



March 5, 1963 A. F. OTTINGER VALVE BAG 2 Sheets-Sheet 1 Filed March 24,1958 30 are 55 XXYKKXXX XXX XXXXX F's 2. 3 XXXXXXEZZXXX jib-U33 3/ %/55d/1 5? KJQ xxxxxxlxxg March 5, 1963 A. F.- OTTINGER VALVE BAG 2Sheets-Sheet 2 xxxxxxxkxxxx XXXXXXXXXXXXX x k-xx- Unite This inventionrelates to bags, and more particularly to valve bags made ofheat-scalable plastic such as polyethylene.

Among the several objects of the invention may be noted the provision ofa bag made of heat-scalable plastic such as polyethylene having a valveat one corner of the bag including an inwardly extending valve extensionfor closing the bag after it has been filled; the provision of a bag ofthis class having such an extension, which may be essentially a papersleeve, of a type which permits free flow of material into the bag froma filling spout inserted in the valve opening and which provides fortight closure of the bag upon removal from the spout after filling; theprovision of a bag such as described which is of such construction as toallow for heat-sealing during manufacture without sticking any part ofthe valve opening and with complete sealing of the end of the bag atwhich the valve is located; and the provision of a bag of the classdescribed in which the extension is of such character as to avoidcontamination of the contents of the bag. Other objects and featureswill be in part apparent and inpart pointed out hereinafter.

The invention accordingly comprises the constructions hereinafterdescribed, the scope of the invention being indicated in the followingclaims.

In the accompanying drawings, in which several of various possibleembodiments of the invention are illustrated,

FIG. 1 is a perspective illustrating a bag having a valve of thisinvention as it appears prior to heat-sealing the bag closed at itsvalved end, parts being broken away;

FIG. 2 is a vertical cross section in the central plane of the valve,showing the bag provided with the heat seal across the valved end of thebag;

FIG. 3 is a view taken on line 33 of FIG. 2;

FIG. 4 is a perspective showing one way in which the valve sleeve may beinitially applied to the bag;

FIG. 5 is a view taken on line -5 of FIG. 4;

FIG. 6 is a plan of the valve sleeve per se;

FIG. 7 is an enlarged cross section, with thicknesses exaggerated, takenon line 77 of FIG. 6;

FIG. 8 is a perspective, with parts broken away and shown in section,illustrating the valve sleeve in a semiflattened condition;

FIG. 9 is a view similar to FIG. 1 showing a modification; and,

FIG. 10 is a view similar to FIG. 2 showing the FIG. 9 modification.

Corresponding reference characters indicate corresponding partsthroughout the several views of the drawings.

Referring to the drawings, FIGS. 1, 2 and 8 show the valve corner of aheat-scalable plastic bag 1 provided with a valve of this invention. Thebag 1 is shown as being formed from a flat seamless tube T ofheat-sealable plastic such as polyethylene (see FIG. 4). The front andback walls of the tube T are designated 3 and 5. The side edges of thetube are constituted by folds 7 of the plastic. The lower end of thetube is closed by a transverse heat seal 8 (see FIG. 4). It will beunderstood that the tube may be a longitudinally seamed tube instead ofa seamless tube.

The tube T is shown in FIGS. 1 and 2 as having at its 3,G&0,lll-ZPatented Mar. 5, 1963 upper right corner a valve formation comprising atuckedin valve corner flap 9. Extending inward from this valve flap 9 isa flexible valve extension constituted by a valve sleeve 11. Thisprojects from the inner end of the valve flap 9 into the bag. As shownbest in FIGS. 6 and 7, the valve sleeve 11 comprises a blank of flexiblepaper 13 (such as kraft paper) coated on one face thereof with a layer13a of heat-scalable plastic such as polyethylene, and coated on itsother face with a layer 13b of a material which is infusible at thefusion temperature of the polyethylene or other heats salable coating13a. Here it will be understood that coating 13b may be an infusiblecoating, such as an infusible lacquer, clay or starch or a coating of amaterial which is fusible but only at a temperature substantially higherthan the fusion temperature of the plastic of the tube and the coating13a, such as a high melting point wax, or a vinyl choride or acetate.The coatings 13a and 13b confine the fibers of the paper layer 13thereby to provide protection against fibers from paper layer 13contaminating the bag contents, and coating 13a additionally serves forheat-sealing the sleeve to the bag tube as will be made clear. The valveflap 9 (which in its entirety is of triangular form) has a central foldindicated at 17 and sleeve 11 is folded in half on a central fold 19 inline with andin extension of the fold 17, folds l7 and 19 being spacedfrom the upper end of the bag tube.

The sleeve if, as shown, is similar, in shape, and also in respect tothe inclusion of a check valve fiap, to the sleeve shown in thecopenrling coassigned application of Russell J. Williams, Serial No.558,542, filed January 11, 1956, issued as US. Patent 2,865,556,December 23, 1958. Thus, the sleeve 11 is shaped to have a base portion21 (corresponding generally to the base portion 21 of the sleeve shownin said patent) but, in accordance with this invention, this baseportion has a total width which is less than the total width of edge 23of the valve flap 9, instead of having a total width corresponding tothe total width of edge 23. The outer corners of the base portion of thesleeve 11 are cut off at a 45 angle as indicated at 25 to match the 45folds 27 on which the valve flap 9 is folded in. The sleeve 11 isinitially folded in half on fold line 19 with the heat-scalable coating13a on the outside (see FIGS. 4 and 5). Then, so folded, it is insertedin the upper end of tube T as shown in FIG. 4 at the upper right cornerof the tube, with the fold at 19 against the right side edge fold 7 ofthe tube. Then, heat-sealing bars (not shown) are applied to the frontand back walls 3 and 5 of the tube to heat-seal the two side portions ofthe folded-in-half sleeve to the inside surface of walls 3 and 5throughout the width of the sleeve as indicated at 29. With thenonsealing coating 13b on the inside of the folded-in-half sleeve,sticking together of the two halves of the sleeve by this heat-sealingoperation is avoided. Then, the valve fiap 9 together with the sleeve 11is tucked in, as illustrated in FIG. 1, the flap 9 being folded in halfon line 17, and sleeve 11 being reversely folded on line 19 in relationto its folded condition of FIGS. 4 and 5 to assume the folded conditionin which it is shown in FIGS. 1 and 2, wherein heat-sealing coating 13ais on the inside and nonsealing coating 13b is on the outside of thefolded sleeve. The 45 corners 25 of the base portion 21 of the sleevelie contiguous to the 45 folds 2.7 on which the valve flap 9 is foldedllIl. Since the total width of the base portion 21 of the sleeve is lessthan the total width of the inner end edge 23 of the valve flap 9, theupper edges Zlle of the folded sleeve are spaced inward from (below) theupper edges 30 of the tube T.

The sleeve 11 has a reduced portion generally desig nated 31 projectinginward from the base portion 21. This portion 31 is folded in half onthe central fold 19 of the sleeve. It is so shaped that, as folded inhalf in the bag,

its two halves have inclined edges 33 which converge toward the centralfold 1% of the sleeve in inward direction (see FIGS. 1 and 2). Theseedges 33 intersect the edges Zlle of base portion 21 at points As shown,edges 33 preferably converge toward the central fold at an angle of 45Portion 31 has a nose 3''? defined by its inner edge 39, which is cutoil at right angles to central told 19, and short side edges 41 paral elto the central fold 1?. The corners of the nose 37 are relieved bycutting them oil at an angle of 45 as indicated at 53.

The sleeve has a longitudinal slit 45 extending in outward directionfrom its inner end to a point spaced inward from the inner end 23 of thevalve flap 9. he slit is located centrally in respect to the width ofthe sleeve in the line of the told 19. it is preferably made with itssides divergent toward the inner end of the sleeve so as to widen towardthe inner end of the sleeve. The corners at the end of the slit arerelieved by cutting them oil at an angle of 135 to the inner end of edge3 as shown at 47. The slit 45 constitutes an opening for flow ofmaterial from the filling spout into the bag in a lateral (downwarddirection with respect to the length or" the sleeve. It is made ofsufiicient length so that the inner end of the sleeve may open up Wideto allow for free how of material from the spout so as to avoidclogging.

The sleeve 11 is provided with a flexible flap #9 con stituting a checkvalve member adapted to permit how of material through the slit 45during the filling of the bag and adapted to close back upon the slit:when the has been filled. As shown, this flap 49 cots of a rectangularpiece of paper with coatings 49a and 4% corre sponding to coatings 13aand 13b having a length greater than the length of the slit and lessthan the distance from the inner end of the sleeve to the inner end ofthe valve flap. It is secured to the sleeve on one side of the slit 4-5as by adhesive 51 to that surface 131) of the sleeve which is on theoutside of the sleeve in the folded condition of the sleeve. The flap 49, as secured to the sleeve, projects laterally with respect to thelength of the sleeve from the portion of the sleeve on the stated sideof the slit in the direction away from the edges 30 (downward as viewedin F168. 1 and 2). The flap 49 extends from a point between the innerend 23 of the valve flap 9 and the outer end 53 of the slit 45 to theinner end of the sleeve. With the sleeve in its flat unfolded conditionas illustrated in FIG. 6, the flap d9 extends completely across the slit45 to overlie the portion of the sleeve on the other side of the slit.The flap 4? is also adapted to over" lie this portion of the sleeve whenthe sleeve becomes flattened on filling the bag (see PEG. 8). When thesleeve is initially folded with coating 13a on the outside (FISS. 4 andfor application to the tube T, the flap lies between the two halves ofthe folded sleeve.

Atiter the valve flap 9 and the attached sleeve 11 have con tucked in,the front and back walls- 3 and 5 of the tube T are heat-sealed togetherby a heat seal 55 (see FIGS. 2 and 8) constituting an end closure forthe tube extending tnansversely across the upper end :of the tube. Asshown, this seal 55 is a seal of substantial Width, and is located sothat its lateral mar-gin 55a toward the end of the tube is outward .ofthe side edge portions lie or" the sleeve its other lateral margin 55bis inward of side edge portions 212. Accordingly, despite the nonsealingcharacter of coating 13b on the outside of the sleeve, the walls of thetube are directly sealed together by the portion 550 of seal 55 whichlies outward of edges 312 so that the upper end of the tube iscompletely sealed. Also, the heat-sealing at 55 results in heat-sealingtogether of the two upper side margins of the sleeve by portion 55d ofthe seal 55 along edges 21a by reason of fusion of the coating 13a(between the two halves of the folded sleeve) adjacent edges 21c. Thus,the portion of the sleeve extending inward from the valve flap is oftubular form. It will be understood that instead of having seal 55looated as shown in FIG. 2, it could, for example, be

cated nearer the upper end of tube T and formed with a wider portion atthe valve corner to effect the heat-sealing together of the uppermargins of the sleeve.

T he bag is filled with finely divided or pulverized material byentering :a filling spout (not shown) into the valve flap 9 anddelivering the material through the spout into the bag. The materialflows tireely into the bag through the sleeve 11 in the direction of thelength of the sleeve and also in .a lateral direction through the slit45. The flap or check valve member 49 :does not impose any perceptibleobstruction to fiow of material into the bag. As the bag is filled, thesleeve flattens out in the manner illustrated in FIG. 8. When the bag iscompletely filled, the flow of material is cut oil and the bag is takenoff the spout. The flattened sleeve is pressed closed by the contents ofthe bag. The flap 49 is pressed closed against the sleeve effectively toblock the slit and prevent escape of material through the slit. Theprovision of the flap 49 makes possible the use of a relatively longslit to ensure tree flow of material into the bag while avoiding thepossibility of leakage through such a slit as may occur without theflap. It will be observed that there is full overlap of the flapthroughout the len th of the slit.

It will be understood that where there is no necessity for insuringagainst contamination of the contents of the bag by paper fibers fromthe sleeve, it is not necessary that the sleeve have the coating 1311.Also, in such case, it is not essential that sleeve 11 have heat-sealingcoating 13a throughout its entire area. It may have a heat-sealingcoating only on the outer end portion thereof which laps the valve flap9. Under such circumstances, there is sufiicient sticking of the upperedges of the sleeve to the bag walls at seal by tusion of theheat-scalable plastic of the bag walls to the paper of the sleeve toprovide the tubular form for the sleeve by reason of the upper edges ofthe sleeve being caught in the seal 5'5.

t will be further understood that the sleeve '11, instead of being madeof coated paper as above described, may be made of heat-scalableplastic. For example, it could be made from sheet polyethylene, and flap4 also made of polyethylene and heat-sealed thereto. If so made,sticking together of the sides of the folded sleeve may be avoidedduring the heat-sealing of the sleeve to the tube T by inserting a sheetof nonheat-sealing material, such as Teflon, between the sides of thefolded sleeve when inserted in the tube T as in FIG. 4.

FIGS. 9 and 10 illust nate a modification in which the sleeve(designated 61 to distinguish it from the sleeve 11) has an outer endportion 63 of triangular shape corresponding to the triangular shape ofthe valve flap 9. End portion 63 laps the valve flap on the outsidesurface of the tube T (instead of the inside surface of the tube as inFIGS. 1 and 2). Also, instead of having the heatsealable coating 13a onthe inside of the folded sleeve and coating 13b on [the outside, thisrelationship is reversed, coating =13a being on the outside and coating1123]] being on the inside. Flap 49 in this instance is secured to thesurface 13a of the sleeve, instead of surface 13b, and this securementmay be by heat-sealing if so desired. The triangular end portion 63 ofthe sleeve 61 is secured to the valve flap 9 as by heat-sealing alongits three sides, as indicated at 65. This triangular end portion servesto stiffen the valve flap. The end of the tube is closed by a heat seal55 the same as that previously de scribed, the only difference beingthat (the upper side margins Zle of the sleeve, instead of beingheat-sealed directly together, are caught in the seal 55, beingheat-sealed to the tube walls 3 and 5 by reason of fusion of the coating13a to the tube walls at 55d. This provides the tubular form for theportion of sleeve 61 which extends in ward from the valve flap.

in View of the above, it will be seen that the several objects of theinvention are achieved and other advantageous results attained.

' As various changes could be made in the above constructions withoutdeparting from the scope of the invention, it is intended that allmatter contained in the above description or shown in the accompanyingdrawings shall be interpreted as illustrative and not in a limitingsense.

I claim:

1. A valve bag comprising a heat-scalable plastic tube, said tube havingan intucked valve flap at one corner thereof, said flap having a centralfold spaced from the respective end of the tube, a flexible sleeveextending inward from the valve flap, said sleeve being folded in halfon a generally central fold in line with the central fold of the valveflap, the outer end portion of the sleeve lapping and being secured tothe valve flap, the total width of said sleeve being less than the totalwidth of the inner end edge of the valve flap and the sleeve having sideedge portions spaced inward from the respective end edges of the tube,and said tube having its walls heat-sealed together by a heat sealconstituting an end closure for the tube extending transversely acrosssaid end of the tube and including a portion located outward of saidside edge portions of the sleeve and a portion located inward of andadjacent said side edge portions of the sleeve, the latter portion ofsaid heat seal constituting a heat seal for said side edge portions ofthe sleeve.

2. A valve bag comprising a heat-scalable plastic tube, said tube havingan intucked valve flap at one corner thereof, said flap having a centralfold spaced from the respective end of the tube, a flexible sleeveextending inward from the valve flap, said sleeve being folded in halfon a generally central fold in line with the central fold of the valveflap, the outer end portion of the sleeve lapping the valve flap, saidsleeve being of heat-scalable character at least where its outer endportion laps the valve flap and being heat-sealed to the valve flap, thetotal width of said sleeve being less than the total width of the innerend edge of the valve flap and the sleeve having side edge portionsspaced inward from the respective end edges of the tube, and said tubehaving its walls heat-sealed together by a heat seal constituting an endclosure for the tube extending transversely across said end of the tubeand including a portion located outward of said side edge portions ofthe sleeve and a portion located inward of and adjacent said side edgeportions of the sleeve, the latter portion of said heat sealconstituting a heat seal for said side edge portions of the sleeve.

3. A valve bag comprising a heat-scalable plastic tube, said tube havingan intucked valve flap at one corner thereof, said flap having a centralfold spaced from the respective end of the tube, a flexible sleeveextending inward from the valve flap, said sleeve being folded in halfon a generally central fold in line with the central fold of the valveflap, the outer end portion of the sleeve lapping the valve flap, saidsleeve being of heat-scalable character throughout the entire area ofone face thereof, said one face of the sleeve engaging the valve flap,said sleeve being heat-sealed to the valve flap and being heat-sealed tothe inside surface of the tube and folded with its said one face on theinside, the total width of said sleeve being less than the total widthof the inner end edge of the valve flap and the sleeve having side edgeportions spaced inward from the respective end edges of the tube, andsaid tube having its walls heat-sealed together by a heat sealconstituting an end closure for the tube extending transversely acrosssaid end of the tube, said end closure being of substantial width andlocated so that its lateral margin toward said end of the tube isoutside of said side edge portions of the sleeve and its other lateralmargin is inward of said side edge portions, the portion of said endclosure heat seal lying inward of said side edge portions of the sleeveconstituting a heat seal for securing together the side margins of thesleeve.

4. A valve bag comprising a heat-scalable plastic tube, said tube havingan intucked valve flap at one corner thereof, said flap having a centralfold spaced from the respective end of the tube, a flexible sleeveextending inward from the valve flap comprising a blank of paper havinga coating of heat-scalable material on the entire area of one facethereof and a fiber-confining coating entirely covering its other face,said sleeve being folded in half in a generally central fold in linewith the central fold of the valve flap, the outer end portions of thesleeve lapping the valve flap, said one face of the sleeve engaging thevalve flap, said sleeve being heat-sealed to the valve flap and beingheat-sealed to the inside surface of the tube and folded with its saidone face on the inside, the total width of said sleeve being less thanthe total width of the inner end edge of the valve flap and the sleevehaving side edge portions spaced inward from the respective end edges ofthe tube, and said tube having its walls heat-sealed together by a heatseal constituting an end closure for the tube extending transverselyacross said end of the tube, said end closure being of substantial widthand located so that its lateral margin toward said end of the tube isoutward of said side edge portions of the sleeve and its other lateralmargin is inward of said side edge portions, the portion of said endclosure heat seal lying inward of said side edge portions of the sleeveconstituting a heat seal for securing together the side margins of thesleeve.

5. A valve bag comprising a heat-scalable plastic tube, said tube havingan intucked valve flap at one corner thereof, said flap having a centralfold spaced from the respective end of the tube, a flexible sleeveextending in ward from the valve flap, said sleeve being folded in halfon a generally central fold in line with the central fold of the valveflap, the outer end portion of the sleeve lapping the valve flap, saidsleeve being of heat-scalable character throughout the entire area ofone face thereof, said one face of the sleeve engaging the valve flap,said sleeve being heat-sealed to the valve flap and being heat-sealed tothe outside surface of the tube and folded with its said one face on theoutside, the total width of said sleeve being less than the total widthof the inner end edge of the valve flap and the sleeve having side edgeportions spaced inward from the respective end edges of the tube, andsaid tube having its walls heat-sealed together by a heat sealconstituting an end closure for the tube extending transversely acrosssaid end of the tube, said end closure being of substantial width andlocated so that its lateral margin toward said end of the tube isoutward of said side edge portions of the sleeve and its other lateralmargin is inward of said side edge portions, the portion of said endclosure heat seal lying inward of said side edge portions of the sleeveconstituting a heat seal securing the side margins of the sleeve to thetube walls.

References Cited in the file of this patent UNITED STATES PATENTS2,034,217 Verwys Mar. 17, 1936 2,437,693 Hartman Mar. 16, 1948 2,676,745Geisler Apr. 27, 1954 2,708,067 Paton May 10, 1955 2,799,314 Dreyer July16, 1957 2,865,556 Williams Dec. 23, 1958

1. A VALVE BAG COMPRISING A HEAT-SEALABLE PLASTIC TUBE, SAID TUBE HAVINGAN INTUCKED VALVE FLAP AT ONE CORNER THEREOF, SAID FLAP HAVING A CENTRALFOLD SPACED FROM THE RESPECTIVE END OF THE TUBE, A FLEXIBLE SLEEVEEXTENDING INWARD FROM THE VALVE FLAP, SAID SLEEVE BEING FOLDED IN HALFON A GENERALLY CENTRAL FOLD IN LINE WITH THE CENTRAL FOLD OF THE VALVEFLAP, THE OUTER END PORTION OF THE SLEEVE LAPPING AND BEING SECURED TOTHE VALVE FLAP, THE TOTAL WIDTH OF SAID SLEEVE BEING LESS THAN THE TOTALWIDTH OF THE INNER END EDGE OF THE VALVE FLAP AND THE SLEEVE HAVING SIDEEDGE PORTIONS SPACED INWARD FROM THE RESPECTIVE END EDGES OF THE TUBE,AND SAID TUBE HAVING ITS WALLS HEAT-SEALED TOGETHER BY A HEAT SEALCONSTITUTING AN END CLOSURE FOR THE TUBE EXTENDING TRANSVERSELY ACROSSSAID END OF THE TUBE AND INCLUDING A PORTION LOCATED OUTWARD OF SAIDSIDE EDGE PORTIONS OF THE SLEEVE AND A PORTION LOCATED INWARD OF ANDADJACENT SAID SIDE EDGE PORTIONS OF THE SLEEVE, THE LATTER PORTION OFSAID HEAT SEAL CONSTITUTING A HEAT SEAL FOR SAID SIDE EDGE PORTIONS OFTHE SLEEVE.